summary refs log tree commit diff
path: root/mm/hmm.c
diff options
context:
space:
mode:
authorChristoph Hellwig <hch@lst.de>2019-06-26 14:27:08 +0200
committerJason Gunthorpe <jgg@mellanox.com>2019-07-02 14:32:44 -0300
commit1e240e8d4a7d92232b6214e02a0a4197a53afd6c (patch)
tree79627ced555b058e23eedd971352ee51918e5dcd /mm/hmm.c
parent3ed2dcdf54d5bf1f9823b5faf1a702e7cee53982 (diff)
downloadlinux-1e240e8d4a7d92232b6214e02a0a4197a53afd6c.tar.gz
memremap: move dev_pagemap callbacks into a separate structure
The dev_pagemap is a growing too many callbacks.  Move them into a
separate ops structure so that they are not duplicated for multiple
instances, and an attacker can't easily overwrite them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'mm/hmm.c')
-rw-r--r--mm/hmm.c10
1 files changed, 7 insertions, 3 deletions
diff --git a/mm/hmm.c b/mm/hmm.c
index 48574f8485bb..583a02a16872 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -1384,6 +1384,12 @@ static void hmm_devmem_free(struct page *page, void *data)
 	devmem->ops->free(devmem, page);
 }
 
+static const struct dev_pagemap_ops hmm_pagemap_ops = {
+	.page_free		= hmm_devmem_free,
+	.kill			= hmm_devmem_ref_kill,
+	.cleanup		= hmm_devmem_ref_exit,
+};
+
 /*
  * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory
  *
@@ -1438,12 +1444,10 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops,
 
 	devmem->pagemap.type = MEMORY_DEVICE_PRIVATE;
 	devmem->pagemap.res = *devmem->resource;
-	devmem->pagemap.page_free = hmm_devmem_free;
+	devmem->pagemap.ops = &hmm_pagemap_ops;
 	devmem->pagemap.altmap_valid = false;
 	devmem->pagemap.ref = &devmem->ref;
 	devmem->pagemap.data = devmem;
-	devmem->pagemap.kill = hmm_devmem_ref_kill;
-	devmem->pagemap.cleanup = hmm_devmem_ref_exit;
 
 	result = devm_memremap_pages(devmem->device, &devmem->pagemap);
 	if (IS_ERR(result))